1. Field of the Invention
The present invention relates to a straightening machine for rolled beams, particularly hyper-beams. The straightening machine includes two straightening disks which are mounted on a straightening shaft and rest against the flanges of the beams from the inside, wherein at least one of the two straightening disks is axially displaceable.
2. Description of the Related Art
A straightening shaft for straightening means of the above-described type has become known from DE-35 22 976 A1. This known straightening machine is used to straighten rails. However, particularly in the case of hot rolled I-beams or hyper-beams to be straightened, it must be taken into consideration that these beams have a constant height dimension in dependence on a series being manufactured, while the flange thicknesses may vary. The use of constant structural heights makes it possible in building construction to use optimized corner connections or gussets of the beams with different section moduli. To make it possible to roll hyper-beams with different flange thicknesses, it is known in the art to adjust the rolling disks of the rolls in the rolling stands of rolling mill trains in such a way that, on the one hand, the constant height dimension of the beams is maintained, while, on the other hand, different flange thicknesses can be rolled. The time required for the adjustment of the roll stand is approximately 30 seconds.
At the present time, straightening in a straightening machine arranged following a rolling mill train is carried out in such a way that the beams are moved into the straightening machine resting on their flanges and the beams then travel with the webs over the straightening disks. This means that the flanges must be plastically deformed during straightening and all required straightening forces are conducted into the flanges through the webs and the transition radii from the webs to the flanges. Since the deformation of the webs also causes breathing of the flanges and an axial force acting on the straightening disks so as to clamp the beam, a construction is required which is stable in axial direction. Therefore, the straightening disks are fixedly mounted on a mounting sleeve and are completely replaced as required. The straightening disks are mounted by means of spacer sleeves or spacer disks which correspond to the internal flange spacing, wherein the internal flange spacing is defined as the distance between the inner surfaces of the flanges which face each other. The mounting sleeve unit is placed directly on the straightening shaft and is axially tensioned by means of a tensioning nut or a chuck. If the internal flange spacing varies as a result of different flange thicknesses, this means that the change-over time is very long because each deviation from the internal flange spacing inevitably results in a change of the mounting sleeve unit.